class_docstr: ECAPA-TDNN encoder. Extracts frame-level ECAPA-TDNN embeddings from
  mel-filterbank energy or MFCC features.
  Paper: B Desplanques at el., ``ECAPA-TDNN: Emphasized Channel Attention,
      Propagation and Aggregation in TDNN Based Speaker Verification,''
      in Proc. INTERSPEECH, 2020.
  
  Args:
      input_size: input feature dimension.
      block: type of encoder block class to use.
      model_scale: scale value of the Res2Net architecture.
      ndim: dimensionality of the hidden representation.
      output_size: output embedding dimension.
code: def output_size(self) -> int:
      return self._output_size
  
file_path: espnet/espnet2/spk/encoder/ecapa_tdnn_encoder.py
imports: import torch
  import torch.nn
  from typeguard import check_argument_types
  from espnet2.asr.encoder.abs_encoder import AbsEncoder
  from espnet2.spk.layers.ecapa_block import EcapaBlock
label_desc: Use image node_id 2 for calling the EcapaTdnnEncoder obj's underlying member method code with example usage: obj.output_size() and returns: self